Conventional industrial gas turbine engines are enclosed by an annular engine casing. Engine casings commonly include a turbine casing, a combustor casing, and a turbine casing bolted together. In a can annular gas turbine engine the combustors are disposed in an annular array about a centerline of the gas turbine engine. These combustors may extend radially outward further than the compressor and turbine components adjacent to the combustors. Consequently, in order to enclose the combustors the compressor casing must bulge radially outward further than the adjacent portions of the compressor and turbine casings. In some designs radially outer ends of combustors extend through the combustor casing and are enclosed with a cap (“top hat”). However, even in casings that utilize top hats, the combustor casing still bulges radially outward. Furthermore, emerging advanced transition designs reposition combustors even further radially outward. Thus there exists room in the art for improved casing design.